Urgent: Interfering Waves Homework: Find Speed in Regions A & B

[kevykevy]

Homework Statement

A plane wave generator with a freqenecy of 60.0Hz creates a water wave of wavelength 3.0cm in region A of a ripple tank. The angle between the wave crests and straight boundary between regions A and B is 25.0 degrees in region A and 14.0 degrees in region B. Find the speed of the wave in each region.

f = 60.0Hz
lambda = 0.030 m
thedaA = 25.0 degrees
thedaB = 14.0 degrees
vA = ?
vB = ?

Homework Equations

I was thinking to use snell's law, but I am not sure how to...

The Attempt at a Solution

General v...

v = f x lamda
v = 60 x 0.030
v = 1.8 m/s

Find vA

vA/1.8 = Sin25/Sin14
vA = 3.14 m/s

Find vB

vB/1.8 = Sin14/Sin25
vB = 1.03 m/s

 

[vanesch]

v = f x lamda
v = 60 x 0.030
v = 1.8 m/s

Yes, so this is already the velocity in region A.

vB/1.8 = Sin14/Sin25
vB = 1.03 m/s

This looks ok at first sight.